diff --git a/content/get-started/workshop/05_persisting_data.md b/content/get-started/workshop/05_persisting_data.md index 5e5864cde4..fb1b925dec 100644 --- a/content/get-started/workshop/05_persisting_data.md +++ b/content/get-started/workshop/05_persisting_data.md @@ -21,43 +21,37 @@ changes won't be seen in another container, even if they're using the same image ### See this in practice -To see this in action, you're going to start two containers. In one container, you'll create a file. In the other container, you'll verify the file exists. -What you'll see is that the file created in one container isn't available in another. +To see this in action, you're going to start two containers. In one container, +you'll create a file. In the other container, you'll check whether that same +file exists. -1. Start an Alpine container and access its shell. +1. Start an Alpine container and create a new file in it. ```console - $ docker run -ti --name=mytest alpine + $ docker run --rm alpine touch greeting.txt ``` -2. In the container, create a `greeting.txt` file with `hello` inside. + > [!TIP] + > Any commands you specify after the image name (in this case, `alpine`) + > are executed inside the container. In this case, the command `touch + > greeting.txt` puts a file named `greeting.txt` on the container's filesystem. - ```console - / # echo "hello" > greeting.txt - ``` - -3. Exit the container. - - ```console - / # exit - ``` - -4. Run a new Alpine container and use the `cat` command to verify that the - file does not exist. +2. Run a new Alpine container and use the `stat` command to check whether the file exists. ```console - $ docker run alpine cat greeting.txt + $ docker run --rm alpine stat greeting.txt ``` You should see output similar to the following that indicates the file does not exist in the new container. ```console - cat: can't open 'greeting.txt': No such file or directory + stat: can't stat 'greeting.txt': No such file or directory ``` -5. Go ahead and remove the containers using `docker ps --all` to get the IDs, - and then `docker rm -f ` to remove the containers. - +The `greeting.txt` file created by the first container did not exist in the +second container. That is because the writeable "top layer" of each container +is isolated. Even though both containers shared the same underlying layers that +make up the base image, the writable layer is unique to each container. ## Container volumes